The first of two episodes with Dr Calder Walton. This one looks at the development of the intelligence war between the West and the Soviet Union from 1917, follows the story through the fulcrum period of the Second World War and pushes on into the intense espionage games of the Cold War.

Based at Harvard's Kennedy Business School, Calder Walton is one of the world's leading experts on intelligence and national security.

We talk about Marx, the Great Illegals and the Cambridge Five. We talk about a US administration which was riddled with spies. How did intelligence affect the Cold War? How crucial was Oleg Gordievsky?

Next time, we will be talking about espionage, Russia and the West, beyond the Cold War.

The conversation is an insight into Calder's brilliant, bestselling book. Just out in paperback, SPIES: The epic intelligence war between East and West, is a masterful and comprehensive look at the incredible story of Soviet and Western espionage. The West, Calder argues, has a long term Russia problem. Christopher Andrew called it 'a masterpiece'.

Buy Calder's book: https://amzn.eu/d/08N5KXb

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